RU2519220C1 - Local hemostatic agent - Google Patents

Abstract

FIELD: medicine.

SUBSTANCE: agent contains chitosan salt 75-95 wt % of polydisperse powders of chitosan hydrochloride, hydrobromide, formate, acetate, succinate, citrate, glycolate or lactate and polyhexamethylene guanidine hydrochloride 4-20 wt %. The chitosan salt and polyhexamethylene guanidine hydrochloride are covalently cross-linked by a polyfunctional compound 1-5 wt % of glycidyl ethers. The chitosan salt is specified with an average particle size of 0.2÷2.0 mm, degree of chitosan deacetylation 0.75÷0.95, and molecular weight 10÷500 kDa. The above polyfunctional compound of glycidyl ethers is presented by a diglycidyl ether of butandiol, di- or triethylene glycol or propylene glycol, oligoethylene oxide, as well as triglycidyl ethers of glycerol or trimethylol propane.

EFFECT: method possesses high blood sorption capacity, rapid hemostasis time and high antimicrobial activity.

3 cl, 2 tbl, 12 ex

Description

The invention relates to medicine, specifically to agents used to stop external bleeding from large blood vessels, and can be used as a local hemostatic agent to protect the lives and health of people exposed to extreme factors.

Known local hemostatic agent for stopping intense arteriovenous bleeding [RU 2414225], including a mixture of synthetic zeolites

CaA type of the formula mCaO · nNa ₂ O · 2SiO ₂ · Al ₂ O ₃ · 0.5H ₂ O and

CaX type of the formula mCaO · nNa ₂ O · 2.5SiO ₂ · Al ₂ O ₃ · 0.5H ₂ O,

whose crystal lattices contain calcium cations in an amount of 8 ÷ 10 wt.% when the ratio of these components, wt.%:

synthetic zeolite mCaO · nNa ₂ O · 2SiO ₂ · Al ₂ O ₃ · 0.5H ₂ O - 70 ÷ 80,

synthetic zeolite mCaO · nNa ₂ O · 2,5SiO ₂ · Al ₂ O ₃ · 0,5H ₂ O - 30 ÷ 20,

and with a ratio n: m equal to 0.13 ÷ 0.22.

The disadvantage of a hemostatic agent based on zeolites is the high temperature, up to 85 ° C, when it comes into contact with blood, resulting in thermal burns of tissues due to heat generation when the zeolite comes into contact with the aqueous medium of blood plasma due to high values of heat of hydration.

Known drug for stopping arterial bleeding based on a mixture of finely divided calcium carbonate, boehmite nanoparticles (aluminum metahydroxide) and polysaccharide [RU 2333002], which does not cause pain and chemical burns of open tissues, which reduces the exothermic effect of hydration and thereby the amount of heat transferred to the wound . The disadvantage of this drug is its relatively low hemostatic efficacy.

A common drawback of these hemostatic agents is the inorganic nature of the main active substance, its biological incompatibility with body tissues and the inability to biodegradation, which can lead to infectious complications.

Patent RU 2471477 discloses the use of a biocompatible complex of chitosan and dioxidine with chlorhexidine for the treatment of purulent wounds with a mass ratio of chitosan succinate with dioxidine 4.25-6: 1 (mass fraction of dioxidine 14.3 ÷ 19.2%) and chlorhexidine 60-85, 0: 1 (mass fraction of chlorhexidine 1.2 ÷ 1.6%), respectively. The complex has a pronounced wound healing effect, which is manifested in the rapid cleansing of a purulent wound and the intensive course of reparative processes. However, the developed material does not have a pronounced hemostatic effect and cannot be used to stop intense bleeding.

A hemostatic agent for topical application is known (WO 2007074326) based on chitosan salts in a mixture with at least one inert material, which does not give heat when mixed with blood, is biologically compatible with body tissues, and has a rather high hemostatic activity.

The disadvantages of such a hemostatic agent are insufficiently high sorption ability in blood, relatively long time of onset of hemostasis and low antimicrobial activity.

In accordance with the above technical solution, a significant part of the finely dispersed powder of chitosan salt (30 ÷ 80%) is replaced by a powder of a material inert with respect to blood (colloidal silicon dioxide, sand, clay, alginate, microcrystalline cellulose, etc.), which leads to improved moisture content blood product and, accordingly, to reduce the time of onset of hemostasis. However, it is obvious that a decrease in the amount of sorbent per unit mass of the drug leads to a decrease in the amount of adsorbed blood and despite the relatively high rate of hemostasis to form an insufficient convolution mass to stop bleeding.

Patent RU 2271814 discloses the use of a biocompatible wound healing agent based on chitosan for the treatment of purulent-necrotic and infected wounds, burns, trophic ulcers. Wound healing compositions contain 62–65% of chitosan, 29–32% of proteolytic enzymes, 5% of ascorbic acid, 0.5–0.75% of trimecaine or pyromicain, and 0.25–0.5% of polyalkylene guanidines from the phosphopag or biopag series. The tool has a combined wound healing, bacteriostatic and immunostimulating property, stimulating regenerative-reparative processes and accelerating the growth of healthy wound cells. However, the developed composition cannot be used as a hemostatic agent, since it contains chitosan in a non-ionized form, not capable of causing the blood coagulation process. At the same time, the mass fraction of polyalkylene guanidines 0.25–0.5% is not high enough to ensure effective stopping of bleeding. This technical solution, the closest in combination of features to the claimed invention, is taken as a prototype.

The technical task of the invention is the development of an effective hemostatic agent of local (local) action with high sorption capacity for blood, short onset of hemostasis and high antimicrobial activity, which is important in providing first and primary health care for stopping parenchymal, venous and arterial bleeding.

The invention is aimed at finding a local hemostatic agent in a series of powdery chitosan salts in a composition with an additive that enhances the operational properties of the developed drug in terms of increasing its blood sorption capacity, reducing the onset of hemostasis and increasing antimicrobial activity.

The technical result of the claimed invention is achieved by the fact that the proposed local hemostatic agent for stopping massive bleeding, characterized by high sorption ability in blood, short onset of hemostasis and high antimicrobial activity, containing a salt of chitosan, which is selected from a number of polydispersed powders of hydrochloride, hydrobromide, formate, acetate , succinate, citrate, glycolate or chitosan lactate, and polyhexamethylene guanidine hydrochloride of the formula:

,

,

where R = N, C ₁₈ H ₃₇ or C ₁₇ H ₃₃ , n = 10 ÷ 20,

wherein the chitosan salt and polyhexamethylene guanidine hydrochloride are covalently crosslinked by a polyfunctional compound from a number of glycidyl ethers in the following ratio of these components, wt.%:

chitosan salt 75.0 ÷ 95.0 polyhexamethylene guanidine hydrochloride 4.0 ÷ 20.0 multifunctional connection 1,0 ÷ 5,0

The technical result is also achieved by the fact that the chitosan salt is selected with an average particle size of 0.2 ÷ 2.0 mm, a degree of chitosan deacetylation of 0.75 ÷ 0.95, a molecular weight of 10 ÷ 500 kDa, and as a polyfunctional compound from a number of glycidyl ethers for the crosslinking of the chitosan salt and polyhexamethylene guanidine hydrochloride, diglycidyl ether of butanediol, di- or triethylene glycol, or polypropylene glycol, oligoethylene oxide, as well as triglycidyl ethers of glycerol or trimethylolpropane are used.

Additionally introduced into the composition of the claimed hemostatic agent polyhexamethylene guanidine hydrochloride is known as a biocompatible, biodegradable and low toxic high molecular weight cationic surfactant with a wide range of biocidal activity [http://polyguanidines.ru]. For the first time, it was found that this compound after covalent crosslinking of its macromolecules with the above glycidyl ethers, along with biocidal activity, exhibits the properties of an effective hemostatic. The mechanism of hemostatic action in this case, apparently, is based on the electrostatic interaction of spatially cross-linked cationogenic macromolecules of polyhexamethylene guanidine hydrochloride with negatively charged erythrocyte cell membranes, as a result of which the erythrocytes stick together to form a dense convolution.

The essence of the invention lies in the fact that the use of covalently crosslinked polyhexamethylene guanidine hydrochloride and a salt of chitosan in the specified range of ratios causes a synergistic effect of the hemostatic composition, i.e. leads to a significant increase in its sorption ability in blood, a decrease in the time of onset of hemostasis and an increase in antimicrobial activity.

The claimed content of polyhexamethylene guanidine hydrochloride is selected in order to achieve maximum efficiency of the hemostatic process and antimicrobial activity of the hemostatic agent. When the mass fraction of polyhexamethylene guanidine hydrochloride is less than 4%, regardless of the degree of crosslinking of the macromolecules (mass fraction of the multifunctional compound), the time of hemostasis increases significantly. An increase in the mass fraction of polyhexamethylene guanidine hydrochloride of more than 20% does not give a synergistic effect of the hemostatic composition and is not economically feasible. In the selected concentration range of polyhexamethylene guanidine hydrochloride an acceptable level of biocidal properties of the composition is achieved.

The claimed content of a multifunctional compound for covalent crosslinking of macromolecules of chitosan salt and polyhexamethylene guanidine hydrochloride is determined from the results of laboratory tests of the sorption ability of the hemostatic composition. When the mass fraction of the multifunctional compound is less than 1%, regardless of the content of polyhexamethylene guanidine hydrochloride, a high level of sorption ability of the composition is ensured, however, the formed blood bundle has insufficient mechanical strength, which leads to its destruction by massive bleeding. With an increase in the mass fraction of polyfunctional compounds of more than 5%, the sorption ability of the hemostatic composition is significantly reduced.

The invention is implemented as follows.

A mixture of powders containing 75.0 ÷ 95.0 wt.% Chitosan salt (for example, chitosan succinate according to TU 9284-027-11734126-08) with a degree of deacetylation of chitosan 0.75 ÷ 0.95, molecular weight 10 ÷ 500 kDa, the average particle size of 0.2 ÷ 2.0 mm and 4.0 ÷ 20.0 wt.% polyhexamethylene guanidine hydrochloride according to TU 9392-020-41547288 with an average particle size of 0.2 ÷ 2.0 mm, is loaded into a 6-fold excess rectified ethyl alcohol according to GOST 51652-2000 containing the calculated amount of glycidyl ether (for example, diethylene glycol diglycidyl ether according to TU 2225-027-00203306-97).

The reaction mixture is heated to a temperature of 50 ° C and maintained at the indicated temperature and vigorous stirring for 4 hours. As a result of the diffusion of glycidyl ether into suspension particles, a heterophase reaction of covalent crosslinking of the macromolecules of polymer salts occurs. At the end of the exposure, the mixture is cooled to room temperature, the excess of ethanol is decanted, and the wet cake is unloaded and laid out on aluminum trays, which are placed in a vacuum drying oven. The product is dried at a temperature of 80 ° C and a residual pressure of 1 ÷ 5 mm Hg column to constant weight. After drying, the finished product is Packed in sealed bags from a combination of packaging material such as Terafol and subjected to radiation sterilization.

The main physico-chemical and medical-technical properties of the claimed hemostatic agents are presented in Table 1.

Table 1 №№ Indicator Value one Fractional composition: wt.%
- number of particles less than 0.2 mm, not more than
- number of particles more than 2.0 mm, not more than 3
3 2 Sorption ability in water, g / g 10 ÷ 25 3 Wetting speed, s, no more 10 3 pH of an aqueous extract, not less 5,0 four Antimicrobial activity (microbial growth inhibition zone according to St. epid. And Ps. Aerog.), Mm, not less 2

The following are examples of laboratory test results of the claimed agent by known methods [patent RU2127428 - a method for evaluating the hemostatic activity of hemostatic matrix preparations of local action, TU 9393-001-18152288-2009 - a method for determining the wetting rate and sorption ability of blood dressings with unilateral and limited contact with liquid, MU of the Ministry of Health of the Russian Federation dated 11/18/83 - laboratory assessment of the antimicrobial activity of textile materials containing antimicrobial preparations], summarized in ABLE 2: "Time to haemostasis, sorption capacity of the blood, and the antimicrobial activity of the claimed hemostat." (Accepted abbreviation: PHMG-polyhexamethylene guanidine hydrochloride).

These examples illustrate but do not limit the proposed technical solution.

To assess the effectiveness of the claimed funds (conventional name "Hemochit"), experimental studies of stopping massive bleeding on rams of the Romanov breed were conducted. The anatomical and physiological parameters of the cardiovascular system (vascular caliber, blood pressure, response to stress factors) ensured the validity of the experiment, in which 8 animals participated. Animals were divided into 2 groups, one experimental - 5 individuals and one control - 3 individuals.

The objective of the experiment was to study the effectiveness of the “Hemochit” agent on a model of severely injured groin with damage to the vascular femoral bundle. In the control group, a pressure dressing was applied to the wound using a service dressing PPI-AV3.

After applying the wound and a short period of uncontrolled bleeding, the drug was poured into the wound, then manual compression was carried out for 10 minutes, after which the adequacy of hemostasis was assessed by the number of recurrent bleeding and the amount of blood loss. The duration of the acute experiment was 180 minutes.

The use of “Hemochit” made it possible to achieve stable primary hemostasis in 4 cases out of 5 (80%). In 1 animal after the resumption of bleeding, “Hemochit” was re-applied with a positive effect. As a result, all animals in the experimental group survived to the end of the experiment. In the control group, all animals died prematurely. The recurrence rate of bleeding was 100%. The volume of blood loss in the experimental group was 400–500 ml, while in the control animals lost an average of 1550 ml.

Thus, the invention opens up the possibility of providing first and primary health care for stopping parenchymal, venous and arterial bleeding with an effective local hemostatic agent based on a biocompatible biodegradable chitosan salt composition with the addition of polyhexamethylene guanidine hydrochloride, which has a high blood sorption capacity and a short hemostasis onset and increased antimicrobial activity.

Claims (3)

Local hemostatic agent for stopping massive bleeding, characterized by high blood sorption ability, short onset of hemostasis and high antimicrobial activity, containing chitosan salt, which is selected from a number of polydispersed powders of hydrochloride, hydrobromide, formate, acetate, succinate, citrate, glycolate or chitosan lactate and polyhexamethylene guanidine hydrochloride of the formula:

,
where R = H, C ₁₈ H ₃₇ or C ₁₇ H ₃₃ , n = 10-20,
while the chitosan salt and polyhexamethylene guanidine hydrochloride are covalently crosslinked by a polyfunctional compound from a number of glycidyl ethers in the following ratio of these components, wt.%:
chitosan salt 75.0-95.0 polyhexamethylene guanidine hydrochloride 4.0-20.0 multifunctional connection 1.0-5.0 2. The local hemostatic agent according to claim 1, characterized in that the chitosan salt is selected with an average particle size of 0.2-2.0 mm, a degree of chitosan deacetylation of 0.75-0.95, and a molecular weight of 10-500 kDa. 3. The local hemostatic agent according to claim 1, characterized in that diglycidyl ether of butanediol, di- or triethylene glycol, or polypropylene glycol, oligoethylene glycol or triglyceride is used as a polyfunctional compound from a series of glycidyl ethers for crosslinking the chitosan salt and polyhexamethylene guanidine hydrochloride trimethylolpropane.